Although there was damage to the casing of the CVR, its memory chip was intact, another NTSC official tells Flightglobal.

"There is 20 minutes of recording and it's being analysed in Indonesia. We've finished downloading it and three translators are trying to verify the information," he adds.

The Sukhoi Superjet was on its second demonstration flight of the day when the incident happened. Radar contact with the aircraft was lost at 14:33 local time, 12 minutes after take-off from Jakarta's Halim Perdana Kusuma Airport.

Before that, the aircraft had requested to descend to 6,000ft (1,828m) and to do a 360 degree orbit right rotation in the training area of Atang Sanjaya, Indonesia's transport minister revealed in parliament this week.